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L.A Nocturne
No full textAbstract
It’s 1984, Los Angeles is on the brink of celebrating the Olympics, and Tony Coletta just got out of San Quentin. Ex Malibu surfer, ex-Vietnam Long Range Scout, ex-psychedelic enthusiast, Tony went inside after a very bad day in 1977. Now, he’s stepping out into a strange new world of neon, new wave, greed and “pro-active” policing. Gone are the easy beach days of the 70s. In these go-go 80s, everyone’s on the hustle, everyone’s making deals and the LAPD is hell bent on “cleaning up the streets”.
These are the opening chapters of LA Nocturne, the first novel in a series featuring Tony Coletta, “just a guy from Malibu” who finds himself pulling the threads on some of the most earth-shattering events in Los Angeles and American history. From the 80s Olympics to the 90s riots and the rise of a rogue element in the LAPD, Tony’s adventures capture the strange unreality of the city of the Angels and the striving energy that endures as the city morphs and grows, mimicking the evolution of America itself.Extension Studie
Exploring the Ribosomal DNA Epigenetic Clock as a Biological Age Estimator
No full textBiological age (BA) is a measure of overall health status that allows one to assess health risks in individuals of the same chronological age. To estimate BA, we need reliable biomarkers of aging (i.e. clocks). Various clocks have been developed with epigenetic clocks being the most widely used. They rely on the age-associated change in DNA methylation (DNAm) to estimate BA. However, they are not evolutionary or biologically grounded. To address this, Wang and Lemos (2019) proposed the ribosomal DNAm (rDNAm) clock, which estimates BA based exclusively on rDNAm. According to them, a biological clock should (1) be evolutionary conserved, (2) have a mechanistic relationship with age, (3) predict chronological age under control conditions and (4) respond to interventions that decrease or increase longevity. In order to explore the rDNAm clock in the light of these criteria, we designed four investigations with each dedicated to one of them. First, we used cohort studies on three vertebrate species to describe how the methylation of rDNA cytosines change with aging and found that only a limited number of them have a positive correlation. We interpret our results as being coherent with rDNAm of early life stages marked by lower methylation levels. Second, we investigated if rDNA is responsive to inflammation using a chicken inflammation trial. We found rDNAm patterns consistent with accelerated aging and, therefore, propose inflammaging as a biological mechanism underlying the rDNAm clock. Third, we tested if the rDNAm clock predicts chronological age in spermatogenic cells. We show that spermatozoa rDNAm is the result of the cumulative effects of mouse chronological aging and sperm development, both of which are captured by the rDNAm clock. Fourth, we demonstrate that exercise modulates rDNAm and that cardiovascular training reverses rDNAm aging. Altogether, we add evidence to the rDNAm clock being a biologically grounded, evolutionary conserved and cost-effective estimator of BA.Population Health Science
Designing Intelligent Interactive Systems for Vulnerable Populations
Get PDFTechnology alone cannot drive social change for vulnerable populations—it amplifies existing human intentions and social forces, sometimes exacerbating inequalities rather than reducing them. This dissertation shows that well-intentioned technological interventions do not inherently benefit marginalized communities and examines how technology can effectively support vulnerable populations when designed to amplify the right forces.
My qualitative analysis of LLM-based mental health chatbots revealed that while these systems offer on-demand, non-judgmental support that boosts user confidence, they face significant limitations in addressing the complex needs of vulnerable users. For LGBTQ+ individuals specifically, these chatbots frequently fail to grasp the nuances of their experiences, providing empathetic but ultimately inadequate support. This demonstrates how technology that merely attempts to ``fix'' missing institutional components without addressing underlying societal factors can widen rather than bridge existing disparities.
To effectively support vulnerable populations, technology must amplify intentional positive forces. Through an experiment on dating interfaces, I demonstrated that supposedly ``neutral'' designs like swipe interfaces perpetuate racial bias, even among users who explicitly claimed not to consider race in their decision-making. By redesigning the interface to display substantive profile information before race information such as photos and names, I significantly reduced biased choices, showing how technology can meaningfully engage willing participants' stated values rather than amplifying implicit biases.
Finally, my work with humanitarian frontline negotiators illustrates how technology can strengthen positive social forces by supporting existing expert practices. Rather than replacing human judgment with AI recommendations, I designed tools that enhance the negotiation process by contextualizing cases and exploring options with associated risks. This approach builds on practitioners' validation practices while augmenting their capabilities to secure essential resources for people in conflict zones.
This dissertation argues that effective technological interventions must identify and strengthen underlying positive social forces while meaningfully engaging willing participants' stated values. By designing systems that amplify these specific elements rather than simply introducing technology as a solution, we can create intelligent systems that genuinely serve vulnerable populations and reduce, rather than reinforce, existing inequalities.Engineering and Applied Sciences - Computer Scienc
Process as Truth: On the Career of Tahara Sōichirō and a Culture of Mass Media Critique in 1970s–2000s Japan
Get PDFJapanese politics went “live” in the 1990s, a turbulent period marked by the collapse of the bubble economy and growing public dissatisfaction with endemic corruption in the ruling Liberal Democratic Party. Criticized for their lack of transparency, politicians found themselves navigating a new and chaotic arena of Sunday morning television debate shows that effectively bypassed the closed channels by which they had historically communicated with journalists. At the forefront of this transformation was journalist and commentator Tahara Sōichirō, whose debate programs Asa made nama terebi! and Sunday Project pioneered the genre. Tahara described his mission at the time as unveiling the previously hidden “process” of politics to the Japanese public through candid debate. The time had come to see inside politics and media.
Critiques of mass media’s relationship with politics, however, e.g., that journalists were embedded in overly cozy relations with politicians—making critical reporting difficult, if not impossible—and that the national newspapers and the semi-public broadcaster NHK’s commitment to “objectivity” or “neutrality” made their coverage deeply unsatisfying, were decades old by the 1990s. Thus, to understand the appeal of seeing politics unfold in a less controlled media environment, it is essential to examine a longer history of journalism in Japan as practiced outside the dominant national newspapers and NHK. This dissertation constructs a genealogy of such “outsider” journalism in magazines and commercial television in 1970s–2000s Japan, one that positioned itself as critical of Japan’s closed mass media structure. At the heart of this journalism was the practice of “media reflexivity,” which I define as the act of acknowledging one’s position within the media to encourage the viewer or reader in turn to consider their own existence inside of media. This reflexivity implicitly posed several radical questions: Why was the established mass media unwilling or unable to communicate knowledge about the process by which it covered or created events? Why could it not speak about itself? I argue that such media reflexivity, as it crystallized in the 1990s debate programs, paralleled the development of “reflexive modernity” in Japan—marked by growing social literacy and precarity in response to economic stagnation and the hollowing-out of postwar social structures.
This dissertation traces Tahara Sōichirō’s career as it developed across four worlds of journalism. Chapter 1 examines 1970s investigative journalism, catalyzed by journalist Tachibana Takashi’s iconic 1974 exposé of LDP leader Tanaka Kakuei in Bungei shunjū. Chapter 2, in turn, assesses the magazine Uwasa no shinsō in the 1980s and the genre of mass media criticism (masukomi hihyō)—a group of publications that sought to reflexively document contemporary media saturation. Chapter 3 explores the influence of television station TV Asahi in pioneering a new form of opinionated “television journalism” in the late 1980s, and the related cultural figure of the anchorman or “caster.” Finally, Chapter 4 and the Conclusion analyze the rise and decline of so-called “telepolitics” in 1990s Japan, assessing how debate programs such as Tahara’s Sunday Project destabilized Japanese politics by injecting spontaneity into political communication. These programs’ influence, however, waned during the Koizumi Junichirō administration (2001–2006), which emphasized Koizumi’s impromptu and “authentic” communication style, thereby allowing the LDP to co-opt many of the criticisms made of its historical relationship with the media. Tahara Sōichirō closely backed Koizumi and served as a media fixer in this transitional period. The dissertation closes with a brief discussion of the legacy of telepolitics in post-Koizumi-era Japan.East Asian Languages and Civilization
The ‘Sprawling-to-Parasagittal’ Transition: Evolution, Function, and Development of the Mammalian Hip Joint
No full textMammals are an ecologically diverse group of animals, yet nearly every extant species has limbs adducted underneath their body in a ‘parasagittal’ posture. In contrast, mammals evolved from ‘sprawling’ synapsid ancestors with limbs splayed out to the side. Despite more than a century’s worth of research, the precise timing and acquisition of mammalian posture along the ‘sprawling-to-parasagittal’ transition remains elusive. Modern technological advancements provide paleobiologists with a new toolkit for revisiting old questions, but the hindlimb has not yet been comprehensively investigated. In this dissertation, I use a multi-disciplinary approach to examine the evolution, function, and development of mammalian parasagittal posture, focusing on the hip joint and associated bones (i.e., pelvis and femur).
In Chapter 1, I focus on direct evidence from the extensive synapsid fossil record by investigating macroevolutionary patterns of pelvis and femur morphology. The evolution of synapsid pelvis and femur morphology included multiple, semi-independent adaptive optima with the largest-in-magnitude change for both bones occurring within prozostrodontian cynodonts and a final pulse of morphological change for the femur among stem therians – the latter of which aligns with evidence from musculoskeletal modeling of the forelimb and hindlimb in a limited number of taxa. The cranially-extended and elongate ilium, reduced pubo-ischiadic plate, and medially offset femoral head show the strongest patterns of change across synapsid evolution – all features associated with a more adducted limb. In Chapter 2, I explore how rarely-fossilized soft tissues (e.g., integument, muscles) constrain hip joint mobility in the extant sprawling tegu and the extant parasagittal Virginia opossum. I found that the integument keeps the distal femur elevated in tegu, preventing more adducted poses, while extrinsic musculature in the opossum prevents the femur from retracting and depressing beyond the extent of poses used in vivo during the stance phase of walking. While ‘deep thigh’ musculature is ancestral for synapsids, mammalian integument evolved at least by Mammaliaformes, if not earlier, and may have permitted more adducted limb poses. In Chapter 3, I explore the evolution of morphogenetic development for the pelvis and femur in the parasagittal mouse compared to the sprawling brown anole and axolotl, and I also compare it to macroevolutionary patterns of morphological evolution in synapsids. Broadly, I found that mouse pelvis and femur morphology is already distinct from anole and axolotl at the earliest cartilaginous stage of development (E13.5) and continues to proceed along a unique morphogenetic trajectory. Further, early stage mouse pelves and femora, potentially as a result of heterotopic change to cranially direct the ilium and medially offset the femoral head, are most similar in shape to eucynodonts and mammaliaforms, respectively, among synapsid subclades.Biology, Organismic and Evolutionar
Elucidating Cellular Dependencies of O-GlcNAc Transferase Structure and Function
No full textO-GlcNAc transferase (OGT) is an essential enzyme and the most conserved glycosyltransferase in humans. Previous studies of OGT at both the cell and organismal level have modulated OGT with genetic deletion, pharmacological inhibition, or RNA interference. These studies utilized methods where phenotypes were scored following prolonged genetic perturbation or probes that exhibited off-target effects. Moreover, the authors attributed phenotypes associated with knockout or knockdown of OGT as being solely due to a lack of glycosyltransferase activity. However, OGT has numerous binding partners and has been observed in multiprotein complexes, suggesting noncatalytic roles that may regulate cellular physiology.
In this thesis, I use next-generation chemical and genetic tools to investigate how changes in OGT’s catalytic and non-catalytic functions alter organellar and cellular physiology. First, I introduce this complex enzyme and previous attempts to define its role in cells. In Chapter 2, I collaborate with a graduate student to investigate how truncations of the tetratricopeptide repeat (TPR) domain of OGT alters its subcellular localization and subsequently cellular viability. In Chapter 3, I present a three-arm chemical genetic screen that separates OGT’s catalytic and non-catalytic synthetic lethal partners. In Chapter 4, I elucidate how a chemical probe that specifically inhibits OGT alters mitochondrial physiology on the scale of hours, suggesting OGT’s essentiality is linked to its role in mitochondrial homeostasis. Finally, in chapter 5 I conclude that OGT’s catalytic functions drive its essentiality and suggest future directions for OGT studies in cells.Chemical Biolog
Studies on the Role of H3K36 Methylation using Histone Mutants
No full textChromatin is coated in a multitude of epigenetic marks of stereotyped distribution and unclear function. Among them, H3 lysine 36 trimethylation (H3K36me3) is enriched around actively transcribed gene bodies from yeast to humans, but its precise role remains disputed. Here, we interrogate the in vivo function of H3K36me3 using an innovative transgenic mouse model that expresses an inducible, dominant negative histone mutation leading to the genome-wide depletion of H3K36me3. Following induction of the mutation, mice became lethally anemic due to a profound differentiation block in terminal erythropoiesis. While H3K36me3 is typically associated with active chromatin, we found that loss of H3K36me3 does not reduce transcription levels, but rather increases transcription from the antisense strand of actively expressed genes. Importantly, these gains in antisense transcripts occurred specifically at genes with basal antisense transcription and robust levels of H3K36me3. Upregulated antisense transcripts triggered an interferon response that resulted in cell cycle arrest and blocked erythroid maturation. We further show that erythroblasts susceptible to elevated antisense transcription have markedly lower levels of DNA methylation and that other tissues are sensitive to antisense transcription when DNA methylation is inhibited. Based on these data, we propose that H3K36me3 and DNA methylation collaborate to repress antisense transcription at active gene bodies in mammals.Biological and Biomedical Science
Stellar collisions in the vicinity of supermassive black holes
No full textGalactic nuclei are unique environments in which dense populations of stars orbit supermassive black holes (SMBHs) at velocities that can reach a few per cent of the speed of light due to the SMBH's gravitational influence. While tidal disruption events (TDEs) have become a common explanation for many luminous flares which originate from this region, direct collisions between such high-speed stars must also occur. Whether those collisions generate transients bright enough to potentially be confused as supernovae (SNe) or TDEs--and, if so, how they might be uncovered in the vast amounts of data generated by modern surveys--forms the central question of this dissertation. To address it, we combine semi-analytic rate calculations, simulations of debris fallback and accretion, and a machine-learning pipeline that is scalable to next-generation surveys of transient phenomena.
This study begins by deriving differential and total collision rates in galactic nuclei. We consider the stellar mass function, velocity distributions, and galactic density profiles to calculate collision frequencies as a function of SMBH mass and collision ejecta energy. For galaxies hosting SMBHs with masses of M_{\bullet}=10^8,10^9,10^{10}\,\Msun, the resulting rates are yr collisions, respectively. We additionally borrow from well-established supernovae models to calculate basic light curves from the collisions; we find that these events can yield luminosities roughly equal to or greater than that from SNe, but the light curves are expected to decay much faster, making serendipitous detection unlikely.
The subsequent fate of the post-collision debris is studied via numerical simulation. Each collision ejecta is represented by millions of freely moving test particles under Schwarzschild geometry; an additional viscous time delay is added to each particle's trajectory assuming an -disk model. Summing over all particles yields mass-accretion rates which are converted to luminosity to generate light curves corresponding to the accretion of the post-collision debris. The light curves that emerge display diverse morphologies--single peaks, double peaks, plateaus, and more--with behavior that depends on physical parameters such as the SMBH mass and initial distance from the SMBH. We find that some of our simulated light curves exhibit behavior that has been previously associated with unexplained TDE phenomena, such as unusual late-time evolution and repeated flares.
We move on to conducting a systematic search for observed nuclear transients that resemble accretion flares from stellar collision debris. We generate a bank containing tens of thousands of simulated light curves with varied SMBH mass, initial distance from the SMBH, and relative velocity orientations. In addition, we have two scaling parameters on the - and - axes, which correspond to a time offset and varied ejecta mass. Observational candidates are obtained from the Lasair alert broker’s Zwicky Transient Facility (ZTF) stream, filtered for nuclear, blue, well-sampled light curves with high signal-to-noise ratio. We implement an approximate nearest neighbor (ANN) algorithm using the \texttt{annoy} (Approximate Nearest Neighbors Oh Yeah) library, which quickly and efficiently matches each observational candidate to a simulated light curve.
Using this pipeline, 26 ZTF transients are found to align well with stellar collision accretion flare models. Host-galaxy photometry and spectroscopy are used to infer SMBH masses whenever possible. Some candidates are found to have , supporting a collision interpretation.
Stellar collisions in galactic nuclei therefore represent a plausible and previously overlooked source of nuclear transients. A collision releases promptly and drives an accretion flare whose properties depend on SMBH mass and galactocentric radius at the time of the collision. The combined analytical, numerical, and data-driven methods presented here provide both predictive observables and a practical identification tool that scales to next-generation survey volumes.
Future work should include magnetohydrodynamic simulations to refine debris structure and accretion physics, the integration of anomaly-detection networks or deep-learning classifiers to improve recall of rare events, and systematic spectroscopic follow-up to separate collision flares from partial TDEs. With the forthcoming data volume from the Vera C. Rubin Observatory’s Legacy Survey of Space and Time (LSST), the tools developed in this dissertation offer a timely approach for recognizing and studying stellar collision transients in the center of galaxies.Physic
Cain
No full textThe autobiography of Cain. The work follows the life of Cain from his own perspective, starting
from his earliest memories and ending with his death. Genesis 4, which contains Cain’s entire
story, can be read in under five minutes, but this material leaves a lot to the imagination. This
work is one way of filling in the blank spaces in the Bible. The work aims to explore Cain’s story
in more psychological depth than the originalExtension Studie
Evaluating Quality of Maternal Health Care in Low- and Middle-Income Countries: Evidence to Inform Policy and Practice
No full textEnding preventable maternal and newborn deaths and realizing the right to health will require expanding access to high-quality care across the pregnancy-postpartum continuum. Progress in driving down maternal mortality has slowed over the past decade of the Sustainable Development Goal (SDG) era, and maternal deaths remain heavily concentrated in low- and middle-income countries (LMICs), particularly in sub-Saharan Africa.1 Access to maternal and newborn care has improved dramatically, but remains uneven across geography and income, and extensive problems with quality undermine the value of care. Maternal health services in LMICs were further impacted by the unprecedented strain of the COVID-19 pandemic on health systems.
This dissertation aims to contribute to a better understanding of the quality of care provided during pregnancy, childbirth, and the postpartum period in LMICs, considering the delivery of evidence-based clinical care and women’s experiences of care. The three studies presented assess gaps in the provision of basic postnatal care for women in Kenya, potential spillover effects of continuous quality improvement for antenatal HIV testing on comprehensive antenatal care (ANC) in South Africa, and women’s decision-making around antenatal and childbirth care-seeking and perceptions of quality of care in Côte d’Ivoire
In Chapter 1, I evaluated the coverage and quality of postnatal care and examined predictors of receiving basic maternal postnatal care among 2,676 postpartum women in eight counties in Kenya. Using longitudinal survey data from the control group of a randomized controlled trial, I found that despite near-universal postnatal care-seeking and coverage of infant-focused measures of care, fewer than one-third of women received basic maternal postnatal care. These findings suggest that postnatal visits in Kenya are often treated primarily as infant check-ups, with many women not receiving a basic standard of care. Mixed effects logistic regression models showed that women who were married and reported always being treated with respect during delivery had significantly higher odds of receiving basic maternal postnatal care, while there was no significant difference seen among women with high-risk pregnancies. Exceptionally high care-seeking in this sample highlights a substantial gap between crude and quality-adjusted coverage, suggesting the need to measure quality of care for both women and infants and ensure that women are provided with a basic standard of postnatal care.
In Chapter 2, I evaluated the potential spillover effect of a nurse-led continuous quality improvement initiative focused on improving two HIV-related components of ANC—viral load monitoring and repeat HIV testing—on the provision of other national guideline-based services for the first ANC visit in a rural and HIV hyperendemic area in Kwazulu-Natal, South Africa. Using data from a pragmatic, stepped-wedge cluster-randomized controlled trial and applying mixed effects Poisson regression, I found no spillover effects—either beneficial or detrimental—of the intervention on the provision of 18 components of care recommended by South Africa’s 2015 national guidelines for maternity care. Regardless of intervention exposure, there were notable gaps in coverage of essential antenatal care services such as symphysis fundal height measurement and iron supplementation. These results suggest that looking beyond vertical quality improvement initiatives aimed at a limited number of services towards more comprehensive and system-level changes may be needed to strengthen the clinical quality of antenatal care more broadly.
In Chapter 3, I explored women’s decision-making around antenatal and delivery care-seeking, and their perceptions and experiences of quality of care within the Taabo Health and Demographic Surveillance System (HDSS) in Côte d’Ivoire. Taking a phenomenological qualitative approach, our team conducted focus group discussions (FGDs) and in-depth interviews (IDIs) with pregnant and postpartum mothers to inform the design and evaluation of future interventions to improve access to high-quality maternal health care in the Taabo HDSS. Despite a national free maternity care policy, unpredictable and rising out-of-pocket (OOP) costs were a major cause of missed and delayed ANC, and further entrenched women’s lack of autonomy in health care decision-making. Lack of information on facility capacity was prevalent, and experience of care—particularly being treated with warmth and respect by providers—predominated women’s decision-making on where to seek care. Our findings indicate the need to design and evaluate interventions addressing the effect of costs on women’s access to care and autonomy, lack of information on facility capacity, and widespread disrespect and abuse of pregnant and postpartum women within the health system.
Considered as a whole, these findings contribute to a growing body of evidence on the quality of maternal health care in LMICs, revealing substantial gaps in the delivery of clinically effective and person-centered care across three geographically and epidemiologically diverse settings and underscoring the need for fundamental health system reform to deliver high-quality care for all women and newborns.Population Health Science